Commius

Commius (Commios, Comius, Comnios) was a historical king of the Belgic nation of the Atrebates, initially in Gaul, then in Britain, in the 1st century BC.

When Julius Caesar conquered the Atrebates in Gaul in 57 BC, as recounted in his Commentarii de Bello Gallico, he appointed Commius as king of the tribe. Before Caesar's first expedition to Britain in 55 BC, Commius was sent as Caesar's envoy to persuade the Britons not to resist him, as Caesar believed he would have influence on the island. However he was arrested as soon as he arrived. When the Britons failed to prevent Caesar from landing, Commius was handed over as part of the negotiations. Commius was able to provide a small detachment of cavalry from his tribe to help Caesar defeat further British attacks. During Caesar's second expedition to Britain Commius negotiated the surrender of the British leader Cassivellaunus. He remained Caesar's loyal client through the Gaulish revolts of 54 BC, and in return Caesar allowed the Atrebates to remain independent and exempt from tax, and in addition appointed Commius to rule the Morini.

However this loyalty was not to last, as related by Aulus Hirtius in the final book of the De Bello Gallico, written after Caesar's death. While Caesar was in Cisalpine Gaul in the winter of 53, the legate Titus Labienus believed that Commius had been conspiring against the Romans with other Gaulish tribes. Labienus sent a tribune, Gaius Volusenus Quadratus, and some centurions to summon Commius to a sham meeting at which they would execute him for his treachery, but Commius escaped with a severe head wound. He vowed never again to associate with Romans.

In 52 BC the Atrebates joined the pan-Gaulish revolt led by Vercingetorix, and Commius was one of the leaders of the army that attempted to relieve Vercingetorix at the Siege of Alesia. After Vercingetorix was defeated Commius joined a revolt by the Bellovaci and persuaded some 500 Germans to support them, but this too was defeated and Commius sought refuge with his German allies.

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